Truck for trailer vehicles



June 26, 1945. L. w. WHITMER TRUCK FOR .TRAILER VEHICLES Filed Aug. 21, 1943 i on the plane indicated by the'line Patented June 26, 1945 UNITED STATES PATENT QFFICTE' TRUCK FOR." TRAILER VEHICLES Lewis W. Whitmer, Columbus, Ohio Application August 21, 1943; Serial No. 499,54r

2. Claims. (01. rise-33m; I

This invention relates to draft trucks for trailer vehicles, and has for an object to provide an load is borne largely by the propelling vehicle,

and since the latter in mostvcases is a standard passenger car, the same is subject to considerable stress and strain for which it was not originally designed to receive. The two-wheel trailer construction, however, does offer the advantage of convenience in forward driving and, therefore, it is one of the outstanding objects of the present invention to provide an improved forward wheeled truck for thetrailer vehicle by means of'which the weight, stresses and strains of the trailer are removed largely from the towing vehicle and yet through the provision of caster wheels on the draft truck, to provide for the same facility in steering and manipulation as has been obtained withthe use of the ordinary two-wheeled trailer.

It is another object of the invention to provide a draft for trailer vehicles which may be readily disconnected from an associated trailer vehicle and used as an independent load-carrying trailer unit. When used independently ofthe trailer vehicle, means are provided for precluding movement of the caster wheels of the draft truck about their vertical axes and to control the efiective length of the tongue structure used in uniting the draft truck with the towing car, so thatbodies of varying length may be supported on a transport by the draft truck. I

For a further understanding of the invention, reference is to be had to the following description and the accompanying drawing, wherein:

Fig. 1 is a plan view of a draft truck for trailer vehicles formed in accordance with the present invention;

Fig. 2 is a vertical transverse sectional view taken through the draft truck on the plane indicated by the line II-II of Fig. 1;

Fig. 3 is a vertical longitudinal sectional view IIIIII of Fig, 1;

pivot 6.

Fig. 4 is a side elevational view of one of the caster Wheels of the truck;

Fig. 5 is a horizontal sectional view taken through one of the coupling members.

Referring more particularly to the drawing, the numeral l designates the axle beam of my improved trailer draft truck. This beam is pref erably in the form of a structural steel member. of channel-shaped cross sectional configuration, the same being formed to embody alowered in termediate portion 2 and relatively elevated outer ends 3 The outer ends of said beam carry rubber tired caster wheels 4, which wheels may be of the type disclosed in my prior Patent No. 2,325,822,,granted August 3,1943, or of other suitable'design. v I I Asillustrated, each of the wheels has its axle. connected with a yoke 51,- the upper end of the yoke being pivoted as at 6 to a head I. The head is formed on opposite sides with laterallyspaced. arms 8, and-between the outer ends of these arms andlugs 9, provided on the yoke 5, are arranged opposed coil springs 10, which yieldably restrict swinging movement of the yokes 5 about the The upper ends of each of theheads 1 vertical fulcrum stud ,l' I; which bearings provided in the outer ends of the axle beam l, permitting ofturning movement of the associated caster wheel about a vertical axis. By means of removable tie rods f2, extending between said caster wheels and the cross beam I, the said wheels may, be prevented from turning about their vertical axes, this feature being desirable when the draft truck isused asan independent load-carrying unit and separated from an associated trailer vehicle,

To unite the axle beam'with an associated pro pelling or towing vehicle, the beam 1 has secured thereto a pair of bars 13. The forward portions of these bars project perpendicularly in-horizontal planes from the beam 1 and are provided with spaced openings 14-. These openings are adapted, to receive at least one set of aligned bolts 15. which are used in pivotally uniting the rear ends of a tongue structure i6 with the cross beam I. The tongue structure, in the specific form illustrated, comprises joined sets of metallic straps ll which converge in a forward, direction and are united together in the longitudinal axis of the draft vehicle, as by welding the same. The joined forward ends of the straps ll provide a seat for the reception of a socket member IS, the socket of the latter being adapted to receive the ball element [9 of the coupling hitch 20, carried by the is provided with a is received within mal plane of operation.

used independently of the trailer vehicle, an extra set of the bolts I 5 may be positioned in the openings'M, as shown by dotted lines in Fig. 1, thereby restricting the tongue to a fixed horizontal position.

The intermediate portions of the bars I 3 are welded or otherwise firmly secured to the beam l and, to the rear of the latter, the bars l3 are angularly bent in inwardly converging directions, as indicated at 2!. To these inwardly bent portions of the bars, there are attached, as at 22, the forward ends of rearwardly converging metallic strap members 23, the latter being joined and united at their rear ends, as disclosed at 24. Positioned upon the rear end 24 of thestrap 23 is a ball element 25, which is adapted to be received within a socket member 26 carried by the frame 2'! of a trailer vehicle 28. Also, the depressed central portion of the axle l carries a fixed ball element 29, which is received in a socket 30 provided at the forward end of the frame 21. The longitudinally spaced ball elements and 29 permit the body of the trailer vehicle to move to a limited extent both vertically and laterally with respect to its nor- However, the employment of the extra element 25 maintains the longitudinal axis of the trailer vehicle perpendicular at all times to the corresponding axis of the beam I, so that the trailer vehicle when being drawn forwardly will maintain a centered position with respect to the beam, avoiding weaving of the trailer vehicle-along the roadway.

Likewise-the use of the dual ball elements 25 and 29 provide for improved control of the trailer vehicle during backing operations or when eXe-. cuting maneuvers in which turns of short radii are necessary or desirable.

As shown in Fig. 5, the socket members I8, 26

or 30 may be provided with confined sliding jaws 3|. These jaws may be formed at one end with arcuate surfaces 3'2 to conform with the configuration of the ball elements, while the opposite ends of said jaws are beveled as at 33. Cooperative with the beveled surfaces of said jaws are the rounded edges 34 provided on the inner ends of pivoted actuating levers 35. These levers are preferably spring pressed as at 36 so that the jaws 3| are normally held in their ball-clamping positions and compensation provided for wear; By a manual operation, the levers may be actuated to permit of the retraction of the jaws 3| and the release of the ball elements associated therewith.

In view of the foregoing, it will be seen that the present invention provides a draft truck for auto-trailer vehicles by which an improved support is provided for the normally unwheeled forward end of such trailer vehicles, enabling the weight of the latter to be sustained by the truck and to relieve the towing car of the stresses and strains imposed thereon when a two-wheeled trailer vehicle construction is used in accomplishing this result, the same facility in steering and manipulation of the trailer vehicle is obtainable as when a two-wheeled trailer vehicle is used through the employment of the freely turning caster wheels on the cross beam. By the use of 'the dual coupling head shown at 25 and 29, the longitudinal axis of the trailer vehicle is maintained in true perpendicular relationship to the corresponding axis of the cross beam l of the draft truck, so that the trailer vehicle does not tend to weave or swing laterally to an undesired extent with respect thereto. Moreover, this dual connection provides greater control over the trailer vehicle during backing operations, enabling the latter to be performed easily and accurately.

The draft truck may be used independently of the trailer vehicle as a separate load-carrying instrumentality. When so used, it is preferable that the tongue It should be held against pivotal movement. If the object carried by the truck when it is used independently should be of excess length, such as in the support of boats, telephone poles or the like, an extension tongue may be united with the forward end of the tongue structure I 6.

I claim:

1. A truck for auto-drawn trailer vehicles, comprising a transversely extending beam having a depressed central region and relatively elevated outer ends, ground-engaging caster wheels carried by and disposed beneath the outer ends of said beam, a tongue structure pivotally united with and projecting forwardly from said beam, a coupling member carried by the forward end of said tongue structure and adapted for detachable connection with the rear of an associated propelling vehicle, a frame carried by and extending rearwardly from said beam, a coupling member carried by the rear part of said frame, and a trailer-coupling member mounted on the depressed central region of said beam and extending upwardly therefrom in longitudinal alignment with the frame-carried coupling member.

2. A truck for auto-drawn trailer vehicles, comprising a transversely extending beam having a depressed central region and relatively elevated outer ends, ground-engaging caster wheels carried by and disposed beneaththe outer ends of said beam, a tongue structure united with and projecting forwardly from said beam, a coupling member carried by the forward end of said tongue structure and adapted for detachable connection with the rear of an associated propelling vehicle, a frame carried by and extending rearwardly from said beam, a coupling member carried by the rear part of said frame, a trailer-coupling member mounted on the depressed central region of said beam and extending upwardly therefrom in longitudinal alignment with the frame-carried coupling member, and means uniting the caster wheels with said beam for precluding turning movement of said wheels about their vertical axes.

LEWIS W. WHITMER. 

